In the background art, there has been known a fuel supply device of an engine provided with a plurality of intake valves and a plurality of fuel injectors (hereinafter referred to as “injectors”) per cylinder (e.g. see Patent Literature 1). In the fuel supply device, the centers of distal end portions of a pair of injectors are disposed on the side of a central axis of the cylinder relatively to central axes of a corresponding pair of intake valves so that fuel can be injected toward the central axis of the cylinder. Thus, even in the case where sucked air flowing into a combustion chamber forms a flow toward the side of an inner circumferential wall (cylinder inner circumferential wall) forming the cylinder, it is possible to prevent spray of the fuel from being easily carried toward the cylinder inner circumferential wall so that it is possible to reduce adhesion of the fuel to the cylinder inner circumferential wall.